强对流云团偏振辐射特性分析

Analysis of Polarization Radiation Characteristics of Strong Convective Cloud Clusters

强对流云团是气象领域重要的研究对象之一。利用大气气溶胶多角度偏振探测仪(DPC)观测数据对强对流云团进行偏振辐射特性研究,为强对流云团识别提供多维信息。以强对流云团、台风云团和非降水云团为例,研究表明:强对流云团反射率高于非降水云团,且其反射率空间分布更均匀;在发展旺盛的强对流云团中大部分是冰晶粒子,只有边缘部分有液态水存在,而其他非降水云团的相态分布差异较大;在相近的照明和观测几何条件下,强对流云团偏振角空间分布的离散性大于非降水云团,且两者偏振角均值差异大;强对流云团的偏振角图像可以很好地表征其轮廓特征。

The strong convective cloud cluster is one of the important research objects in the meteorology field.The polarization radiation characteristics of strong convective cloud clusters are studied by using the observation data of the atmospheric aerosol multi-angle directional polarimetric camera(DPC),which provides multi-dimensional information for the identification of strong convective cloud clusters.Taking strong convective cloud clusters,typhoon cloud clusters,and non-precipitation cloud clusters as examples,the research shows that the reflectivity of strong convective cloud clusters is higher than that of non-precipitation cloud clusters,and its spatial distribution is more uniform.Most part of the developing strong convective clusters are ice crystal particles,and only the edge part has liquid water,while the phase distributions in other non-precipitation clouds are quite different.Under similar illumination and observation geometry conditions,the dispersion of the polarization angle spatial distribution of the strong convective cloud clusters is larger than that of non-precipitation cloud clusters,and there is a large difference between the average of polarization angles.The polarization angle image of the strong convective cloud cluster can well characterize its contour characteristics.